shepherd



entre@ sfrafrns Parana ernten.

WM. SHEPHERD, JR., OF BROOKLYN, NEXV YORK, ASSIGNORv TO THOS. HOLMES ANDVAN VVYCKv FOSTER, OE SAME PLAGE.

VALVE Eon STEAM-ENGINES.

Specification of Letters Patent No. 23,885, dated May 3, 1859.

To all whom it mayfconcem:

Be it known that I, l/VILLIAM SHEPHERD, Jr., of Brooklyn, EasternDistrict, in the county of Kings and State of. New York, have inventedan Improvement in Valves for Steam-Engines, the construction andoperation of which I have described in the following specification andillustrated in its accompanying drawings with sufficient clearness toenable competent and skilful workmen in the arts to which it pertains oris most nearly allied to make and use my invention.

My invention relates more particularly to that class of engines whichare used for pumping water by means of a direct attachment of the engineto the pump, though it is believed that it may be applied with advantageto some other engines. In these engines for pumping, a valve has beenoperated by the direct action of the piston rod, which valve eitheradmits and cuts off the steam to and from the cylinder, or admits andcuts off steam to operate one that does. Till recently the former modeof operating has been the one employed.

In the patent granted to Robert H. Fletcher the 15th dayrof September,1857, an invention is described in which the valve which controls theadmission of steam to the cylinder is operated by the direct action ofsteam which is admitted to work it, by means of another valve which isoperated by the direct action of the piston rod. The operation of thisdevice, while in the main, satisfactory, is, nevertheless, open to theobjection of the slamming of the valves at the end of each valve stroke,which besides abrading and destroying the parts, makes an amount ofnoise which is exceedingly unpleasant. To prevent this slamming of thevalve is the object and purpose of my invention.

In the patent of Edward G. Barrett J anuary 19th, 1858, an invention isdescribed' which is intended to accomplish the same purpose by an arrayof devices, which, while it might produce the result, isnotwithstanding, too complicated and difficult to construct and keep inrepair to give general satisfaction.

My invention consists in the combination of a cover attached to andoperated by the valve which directly controls the admission of steam tothe cylinder, with ports, entering the valve cylinder, in such a way asto furnish, in the manner hereafter described, a cushionA of live steamto restrain the valve at the end-of the stroke and prevent its slamming;

My said invention is represented in the accompanying drawings asfollows: Figure 1, is a longitudinal sectional elevation of my valve,with a portion of the cylinder and concomitant parts. F ig. 2, is atransverse sectional elevation of the valve. Fig. 3, is a plan. Theparts are shown in a central position.

A is the cylinder of the engine, which is made in the usual manner withsteam passages ,-a, and exhaust as shown.

B is the piston.

C is the valve, which by being operated as hereafter described,controlsthe admission of the steam to the cylinder A to act upon the piston.This valve is in most respects constructed very much like that of Mr.Fletcher described in his patent of September, 1857, above referred to.

D, D', are the pistons against which steam is admitted to move the valveC; E, E', are the cylinders in which these pistons operate; c, e, arethe passages through which the steam to operate the pistons D, D, isadmitted into the cylinders E, E; F is a valve, by the operation ofwhich this admission of steam is controlled.

So far the apparatus does not essentially dilfer from what had beenknown and used before. To prevent however the valve C from slamming atthe ends of itsstroke, I make small passages f, f, into the cylinders E,E', and so arrange these passages in connection with the cover G whichis operated by the valve C, (it being for that purpose supported in arecess in or on lugs which form a part of the side pieces H whichconnect the parts of the valve C) that as the valve C approaches the endof its stroke, the passages f, or f are opened to admit steam upon thevalve piston D or D, whichever may be advancing, and this cushion actsin such a manner as to prevent the valve from slamming.

An ,inspection of the drawings will give a very clear idea of theconstruction of the parts and their operation. It will be cbserved thatas the receding piston D or D approaches its limit of travel, it opensthe exhaust port g or g', which is connected with the main exhaust b bythe exhaust la, thus allowing steam to escape from the receding pistonsuiciently to relieve it from heavy pressure, though the exhaust portsg, g', are, as a matter of economy, made small. The exhaust 7L receivessteam through the valve F, from the cylinders E, E. I is the piston rod,which operates the valve F.

By the arrangement above described, the slamming of the valve iseffectually prevented, and the operation of the parts rendered smoothand easy.

Having thus fully described my said invention, I Wish it distinctlyunderstood that I do not claim the prevention of the slamming of thevalve Without reference to the

